1. Field of the Invention
This invention relates generally to swimming pool vacuum cleaners and more particularly to a hydrofoil attachment for improving the positioning of the vacuum cleaner against the pool surfaces.
2. Description of Related Art
One device which is widely used in cleaning the submerged surfaces of swimming pools is a vacuum cleaner. The vacuum cleaner has a head which may be supported by a plurality of wheels to keep the edges of the head only slightly above the pool surface. A hose, connected at one end to a vacuum and filtering system, is connected to the vacuum cleaner head to draw water and debris under the edges of the head to be carried for filtering. The vacuum cleaner head is moved by a maneuvering a long pole pivotally connected to the head. When the head is being pushed by the person standing on the edge of the pool, part of the thrust exerted tends to maintain all of the wheels of the vacuum cleaner head on the pool surface. When the head is being pulled back, however, the wheels tend to lift off the pool surface and the vacuuming effect is lost or substantially reduced. The backward stroke of the vacuum head is consequently essentially wasted as a cleaning stroke.
In the past the difficulty of maintaining a cleaning device against a submerged pool surface during both pushing and pulling strokes has been recognized, and solutions have been proposed.
U.S. Pat. No. 3,003,168, Shouldice, entitled: "Underwater Brush" discloses a water foil which is pivotally mounted on a brush backing vane. The foil has a larger area above the pivot than below the pivot in order to move the foil to the proper position.
U.S. Pat. No. 3,402,413, Gibellina, entitled: "Swimming Pool Brush Guide" discloses a guide designed to produce downward force on a brush during the pushing stroke and lifting force during the pulling stroke.
U.S. Pat. No. 4,637,087, Feinberg, entitled: "Swimming Pool Cleaner Attachment" discloses a water foil which is attached to a swimming pool cleaning brush. The foil is attached in a fixed position, but it includes openings which are closed by a flexible flap when the brush is pushed, and which are forced open by the flow of water when the brush is pulled. This structure is directed to aiding in the brushing of the vertical walls of a pool and performs its function during the pushing stroke.
It is therefore an object of this invention to provide hydrofoil apparatus for use with a swimming pool vacuum cleaner which will aid in keeping the vacuum cleaner head in proper operating position during the pulling stroke.
It is also an object of this invention to provide hydrofoil apparatus which is readily attached to conventional swimming pool vacuum cleaner heads.
In accordance with these and other objects, which will become apparent hereafter, the instant invention will now be described with reference to the accompanying drawings.